When people say sex sells, most of the time what they really mean is that sexy women sell.

For decades, advertisers have been finding different ways to feature women in ads in order to entice buyers. And, it would seem, the strategy works.

But the way women have been portrayed in advertising has changed over the decades, and changed the way society views women because of it. From housebound drudge to sexpot to business leader, ads are constantly arguing with us about women's role in society.

Here's how advertisements featuring women have shifted throughout the last century.